The present invention relates to a semiautomatic control system and a method for vehicles.
When journeys are made with vehicles, in particular rail vehicles, numerous peripheral conditions must be taken into account in order to determine control commands such as accelerating, braking or the definition of setpoint speeds. The peripheral conditions are, for example, a general travel schedule, temporary characteristics (for example owing to roadworks or engineering works), signalling devices, specified values set by a control centre, the topology of the route, weather influences and vehicle-specific peripheral conditions such as the mass of the vehicle or traction mass, maximum power and maximum speed. Furthermore, remaining degrees of freedom can be utilized in order to optimize the driving method, for example with respect to minimum energy consumption or minimum wear.
For this reason, it is suitable to use an automatic control system to provide support for a human driver of the vehicle.
Two different categories of control systems are conventionally known for this:
1. Manual control system with auxiliary means
An example of such a control sequence is shown in FIG. 4. In such control systems, on the one hand automatic control actions or control data are determined automatically in a control device by reference to predefined peripheral conditions (step S41a) and displayed to the driver of the vehicle as decision suggestions on a display device (step S42a). In step S41m, the driver of the vehicle inputs control data to an input device, either taking into account the displayed decision suggestions for the control data or not taking them into account. In step S42m, the vehicle is then controlled in accordance with the control data which had been input.
2. Fully automatic control system with manual intervention feature
The control sequence in such a control system is shown in FIG. 5. In such control systems, automatic control actions are applied directly. In step S51, control data for the vehicle are determined automatically with reference to predefined peripheral conditions. This automatically determined control data is output directly to the vehicle control device in step S53, without the driver of the vehicle having access to this control data. However, it is still possible for the driver of the vehicle to intervene manually (step S52) in situations relating to safety (emergencies) by inputting control data.
The first category of control systems, i.e. manual control systems with auxiliary means, is mostly found in contemporary implementations of a driving method which is optimized in terms of energy.
For example, in xe2x80x9cDevelopment of an on-board energy saving train operation system for the shinkansen electric railcarsxe2x80x9d by Shinobu Yasukawa, Shinichiro Fujita, Takehisa Hasebe and Koichi Sato in Quarterly Reports of RTRI, Tokyo, 28(2-4):54-62, 1987, and in xe2x80x9cRechnergestxc3xctzte energiesparende Fahrweise im Regelbetriebxe2x80x9d [Computer-assisted, energy-saving driving method in closed-loop control mode] by Gerhard Voss and Dirk Sanftleben in xe2x80x9cETRxe2x80x94Eisenbahntechnische Rundschauxe2x80x9d [Railway periodical], 47(1):25-31, 1998 a manual control system is described in which times for starting roll-out phases are suggested to the driver of the vehicle by means of an LED. The publication mentioned first additionally discloses that speed suggestions should be displayed, making it possible for this information to be output on a display device, for example a screen.
The second category of control systems, i.e. fully automatic control systems, has hitherto been applied principally in experimental trials. For example, in xe2x80x9cEinfluss der Fahrtechnik auf den Energieverbrauch eines Personenzugsxe2x80x9d [Influence of driving technique on the energy consumption of a passenger train] by Bozetech Sula in Elektrische Bahnen [Electric railways], 88(4):192-198, 1990 a comparison is made between manual and automatic operation, i.e. manual and fully automatic control systems. Here, it is determined by means of trials that the most energy saving driving method can be achieved with completely automatic control. A travel optimizer with a speed controller, a device for target breaking and a device for programmed control of the journey are used to perform control. Within the scope of these investigations it has been recognized that travelling using xe2x80x9cauxiliary meansxe2x80x9d, i.e. suggestions given by the travel optimizer, is relatively demanding for the driver of the vehicle because it is necessary to follow the readings of the measuring devices and the kilometer markings very strictly. In addition, when performing manual operation in response to suggestions it is not possible to achieve such fine gradation corresponding to the situation in which it has occurred.
In European patent application EP 0 755 840 A1, a method and a device for optimizing the driving method of a vehicle, preferably a rail vehicle, is disclosed. Here, both aforementioned categories of control systems are applied. Route data are permanently stored in a computing device before and/or during the journey. During the journey, dynamic status data relating to the distance and/or speed of the vehicle are recorded and fed to the computing device. A recommendation for a driving method which is optimized in terms of energy and/or as wear-free as possible is computed from said data. The computing result is displayed to the driver of the vehicle on a display device. The possibility of using these computing results directly for actuating the vehicle drive is also disclosed, so that a fully automatic control system is obtained in which the vehicle driver can intervene for safety reasons, but is not intended to do so during normal operation.
As a rule, the journey is monitored by safety devices in all control systems. For example, in the publication mentioned above xe2x80x9cDevelopment of an On-Board Energy-Saving Train Operation System for the Shinkansen Electric Railcarsxe2x80x9d a method of monitoring the speed is described in which when a permitted maximum speed (threshold value) is exceeded, automatic braking to a speed below this threshold can be initiated.
In the conventional manual control systems with auxiliary means described above it has, however, proven problematic that the human driver of the vehicle, who must in any case take into account numerous peripheral conditions and display instruments, must absorb and process additional information. This leads to additional loading. In addition, a computed optimized driving method may only be unsatisfactorily implemented owing to reading errors and time delays which inevitably occur. Furthermore, the driver of the vehicle may feel that these auxiliary means of the manual of control system are demotivating in that the decision suggestions remove the need for him to exercise his own initiative.
Such disadvantages no longer occur in a fully automatic control system such as is proposed in EP 0 755 840 A1, for example. In the publication cited above xe2x80x9cEinfluss der Fahrtechnik auf den Energieverbrauch eines Personenzugsxe2x80x9d [Influence of the driving technique on the energy consumption of a passenger train] it has even been shown that a driving method which is optimized in terms of energy can be implemented better in an automatic mode by means of a fully automatic control system.
However, the direct application of automatic control actions which are determined has the main disadvantage that they may be incorrect owing to peripheral conditions which are possibly only unsatisfactorily taken into account by the automatic control system. For this reason, it is currently not yet possible to dispense with the driver, and the driver has the task of monitoring, and if appropriate, intervening in the fully automatic control system, as proposed in EP 0 755 840 A1. However, this can lead to reduced attentiveness of the driver during a relatively long period of automatic operation, and thus entails, inter alia, the risk of in particular situations in which the driver should in fact intervene being overlooked. The direct application of automatic control actions which are determined is also a practical disadvantage because existing safety concepts for the automatic operation which is carried out with them has to be revised.
For this reason, the object of the present invention is to design a semiautomatic control system and control method with which a driving method which is optimized in terms of energy can easily be achieved without losses in attentiveness of the driver of the vehicle inevitably occurring, and without existing safety concepts having to be revised.
It is thus ensured in a simple manner that both a computed optimum control means is precisely implemented and nevertheless the driver of the vehicle remains attentive during the entire journey. Furthermore, possible errors by the driver of the vehicle can be corrected by the semiautomatic control system or control method.
These and further objects, advantages and features of the invention are apparent from the detailed description below of a preferred exemplary embodiment of the semiautomatic control system according to the invention and control method according to the invention in conjunction with the drawing.